You can install and remove packages as and when you want to, and you can choose whether to install free or non-free software on your system.

你可以随心所欲的安装或者移除软件包，选择在你的系统上安装自由软件还是非自由软件。

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GPL version 2, in 1991, was designed also to prevent patent holders from using their patents to impose licenses on redistributors in a way that would make the software non-free.

1991年第2版GPL的设计，同样是为了防止持有专利者利用他们的专利权以某种会使软件变得非自由的手段强加许可协议给重发布者。

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This third-party repository gives us access to all kinds of non-free software such as Adobe Reader, Skype and codecs for restricted media formats.

第三方软件仓库给使我们可以获得非自由软件，例如adobe Reader, Skype和受限格式的解码包。

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For the free software movement, however, non-free software is a social problem, and the solution is to stop using it and move to free software.

FORBES: Free Versus Open: Does Open Source Software Matter In The Cloud Era?

It says that non-free software is an inferior solution to the practical problem at hand.

FORBES: Free Versus Open: Does Open Source Software Matter In The Cloud Era?

But now, GreenPrint is offering a free version of the software for non-business use, supported by advertising.

CNN: Software saves trees, cash and headaches, says creator